In a case of life imitating art, Birdmansoared in its bicoastal debut for former Batman star Michael Keaton, who plays a washed-up superhero movie star trying to rehabilitate his career by launching a show on Broadway.

The dark comedy, from director Alejandro G. Inarritu, grossed an estimated $415,000 from four theaters in New York and Los Angeles for a whopping screen average of $103,750, the best showing so far this year after Wes Anderson's The Grand Budapest Hotel, which posted a record-breaking theater average of $202,792 earlier this year. (This year's other indie hit, Boyhood, posted a screen average of $77,524 when launching in five locations in July.)

It's also one of the best showings in two years if Sunday's estimates hold. Birdman, hoping to be a prominent awards player, now has to hold up as it wings its way into other top markets.

"I think to see him in this part was really gratifying for people," said Searchlight distribution chief Frank Rodriguez.

Keaton's box office record has been decidedly mixed over the last two decades since starring in Batman Returns in 1992 and Batman in 1989.

Birdman isn't Keaton's first indie effort. He both directed and starred in the 2008 drama, The Merry Gentleman, which quickly disappeared, opening to $74,981 in 24 theaters and topping out at $347,000.

Two years earlier, Keaton played the lead in indie film Game 6, which fared even worse, opening to $9,610 from four theaters for an average of $2,402. Game 6 also starred Keaton as an aspiring playwright, although in that film, his character sets out to kill a critic who skewered his last play.

Rodriguez said Birdman's strong opening was the culmination of several factors, including stops at the Venice, Telluride and New York film festivals, and a massive publicity blitz by the cast in the days leading up to the movie's release.

"It's also a cinematic triumph," said Rodriguez, in reference to Inarritu and Gravity cinematographer Emmanuel Lubezki's decision to make the movie seem as if it was shot in one long take.

While an ode to Broadway, Birdman's top-grossing theater was the Arclight Hollywood in Los Angeles, followed by the Angelika Film Center in New York, the Landmark in Los Angeles and Lincoln Square AMC in New York. Next weekend, Birdman opens in an additional 18 markets, including San Francisco, Seattle, San Diego, Boston, Washington, D.C., Detroit, Chicago, Atlanta and Dallas.

Elsewhere at the specialty box office, Roadside Attractions and Justin Simien's satirical dramedyDear White People enjoyed a strong start, earning $338,000 from 11 theaters in select markets for a location average of $30,702.

Dear White People, premiering at the Sundance Film Festival in January, follows four African-American students at an Ivy League university whose lives converge when controversy erupts over an African-American themed Halloween party thrown by white students. The film stars Tyler James Williams, Tessa Thompson, Teyonah Parris, Brandon P. Bell and Kyle Gallner.

Elsewhere, Alex Ross Perry's 2014 Sundance entryListen Up Philip, starring Jason Schwartzman, Elisabeth Moss and Jonathan Pryce, opened in two theaters, grossing $24,291 for a so-so location average of $12,146 for Tribeca Film.

Among holdovers, Bill Murray's comedy St. Vincent expanded into a total of 68 theaters in its second outing, grossing $685,000 for a location average of $10,074 and a cume of $836,982.

"St. Vincent is working very well in the suburbs, so we are going to pull the trigger next weekend and go wide," said TWC's Erik Lomis. "People are embracing it because it's a feel-good movie. There's a lot of heavy stuff in the market."

Fox International's co-production Bang Bang celebrated the weekend by becoming the top-grossing Bollywood title of all time in North America, not accounting for inflation. The film earned $155,000 from 108 theaters for a domestic total of $2.6 million, surpassing last year's Kick ($2.5 million).